Rapid determination of intervisibility between two locations based on Digital Terrain Elevation Data (DTED) is needed for many applications, such as ad-hoc networking and real-time flight planning. These applications may need intervisibility determination for different reasons. For example, to have a robust communication between two nodes in an ad-hoc networking environment, a clear Line-Of-Sight (LOS) between these two nodes is needed. Since there may be many communication nodes (ex. —200 nodes) in an ad-hoc network, it is critical to determine intervisibility rapidly between these many nodes so messages can be transmitted reliably from the starting node to its remote destination node by jumping through many intermediate nodes. For the real-time flight planning applications, it is essential to plan a safe and shorter path for threat avoidance by ensuring there is no intervisibility between the modified flight path and threats, especially when the flight path penetrates through threat zones. In other words, a safe and shorter path can be constructed by hiding behind terrain so that threats cannot see the aircraft, even when the aircraft is within threat zones.
Intervisibility computation with DTED terrain files is a time-consuming process, especially when many intervisibility computations (ex. —100,000 computations) are needed to construct a safe and terrain-masked path. Therefore, applications requiring extensive intervisibility computations are currently performed on ground facilities that have access to fast computational devices, since airborne platforms usually lack the required computational resources to perform many intervisibility computations in a very short period of time required to support mission objectives.
However, many airborne applications are starting to demand the capability of rapid intervisibility computations so that locations of communication nodes may be adjusted or flight paths may be re-planned in-flight to take into account real-time unforeseen events. Current intervisibility algorithms may not operate efficiently in resource-constrained airborne platforms.
Thus, it would be desirable to provide a method for rapid intervisibility determination which implements an algorithm which performs efficiently in resource-constrained computational environments and obviates problems associated with current solutions.